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101.
In the present article we characterized the emissions at the exhaust of a Common Rail (CR) diesel engine, representative of lightduty class, equipped with a catalyzed diesel particulate filter (CDPF) in controlled environment. The downstream exhausts were directly analyzed (for PM, CO, CO2, O2, HCs, NOx) by infrared and electrochemical sensors, and SEM-EDS microscope; heavy metals were chemically analyzed using mosses and lichens in bags, and glass-fibre filters all exposed at the engine exhausts. The highest particle emission value was in the 7–54 nm size range; the peak concentration rose until one order of magnitude for the highest load and speed. Particle composition was mainly carbonaceous, associated to noticeable amounts of Fe and silica fibres. Moreover, the content of Cu, Fe, Na, Ni and Zn in both moss and lichen, and of Al and Cr in moss, was significantly increased. Glass-fibre filters were significantly enriched in Al, B, Ba, Cu, Fe, Na, and Zn. The role of diesel engines as source of carbonaceous nanoparticles has been confirmed, while further investigations in controlled environment are needed to test the catalytic muffler as a possible source of silica fibres considered very hazardous for human health.  相似文献   
102.
共有财产资源产权结构的特点与利用行为   总被引:10,自引:0,他引:10       下载免费PDF全文
分析了共有财产资源产权不具有排它性、交易双方产权拥有不平衡性和产权不具有转让性的产权结构特点,由此决定了共有财产资源在使用时具有公开获取性,在使用结果上具有排它性,而且个人使用的收益总是大于个人分担的成本.在此基础上,如果共有财产资源向每个使用者开放,没有计划地使用,就会导致过度利用、早用及至误用资源。要防止这种情况发生,只有从控制共有财产资源的使用、加强共有财产资源的管理着手.  相似文献   
103.
草地被称为世界性的公共资源。以往对于草地退化的关注多侧重在技术研究和推广上。为揭示微观行为对公共资源利用的影响,以寻求有效途径保护具有重要生态战略意义的草地资源,论文利用2005年西部6省区17县231个农户数据以及2006和2007年环青海湖地区的实地调查经验,采用农户模型和计量分析方法,研究现有产权制度下牧民的草地管理行为对草地资源退化的影响。结果表明,牧民参与非农就业、扩大牧户的草场规模以及进行围栏和舍棚建设有利于减轻草场的退化。据此,提出以下政策建议:目前政府提供围栏和舍棚建设方面的相关政策扶持,同时,制定有利于牧民参与非农就业机会的政策,降低牧区的人口压力,可有效促进草地公共资源的可持续利用。  相似文献   
104.
The present study focused on the assessment of oxidative stress induction by pesticides such as carbamates which are widely used as insecticides and nematicides and contaminate aquatic ecosystems on certain biomarkers in liver of common carp (Cyprinus carpio L.). Biomarkers selected for stress monitoring were malondialdehyde (MDA), an index of lipid peroxidation, and antioxidant defence system enzymes, mainly catalase (CAT), glutathione reductase (GR), and glutathione-S-transferase (GST) activities in liver of fish exposed to 0, 10, 50, or 100?µg?L?1 of carbofuran for 4, 15, or 30 days. Oxidative stress was found in liver of common carp exposed to carbofuran which was manifested by a decrease in CAT and GR activities after 4 and 30 days of exposure. An adaptive response was probably produced since at day 15 no modifications in the CAT activity and increased GR activity were observed. In addition, a decrease in MDA content with the highest concentration of carbofuran used was found after 30 days of exposure. However, no significant changes were found in GST activity showing a varied response. The results concerning oxidative and antioxidant profiles indicate that subchronic exposure to the insecticide carbofuran is capable of inducing oxidative stress in fish.  相似文献   
105.
This paper aims to assess the impacts of household behaviour on social sustainability by simulating agricultural policy scenarios of the European Union (EU) Common Agricultural Policy (CAP). For this purpose a multicriteria model was formulated, at farm household level, in order to study the social impacts of the CAPs using different scenarios. The scenarios were chosen on the basis of the main EU policies affecting farm households, such as the alternative crops scenario, the Water Framework Directive scenario and the agrienvironmental schemes scenario. The data for this analysis resulted from the CAP-IRE project, a European FP7-funded project. The model includes a utility function with several conflicting criteria such as maximization of gross margin and risk and labour minimization. The model is further used to simulate the impacts on social sustainability by estimating main social indicators. The model is applied in two different farm types in Greece. The results show that the CAP scenarios have multiple social impacts on agricultural holdings, and particularly on the farm labour structure. These impacts have negative effect on social sustainability.  相似文献   
106.
资源开发利用与可持续发展的关系   总被引:1,自引:0,他引:1  
在可持续发展思想的基础上 ,讨论了公开性与共同性原则 ,论述了在资源开发利用过程中公开性、共同性与可持续发展的关系 ,并提出了开发措施。  相似文献   
107.
本文对卫星定位汽车行驶记录仪按DB44/T578-2009测试时常见不合格问题及对策进行简要的分析,解决这些问题对设计和测试卫星定位汽车行驶记录仪是很有必要的。  相似文献   
108.
小流域是实现重点流域精准化治理的基本单元,"三生共赢"是指要把解决环境问题的目标定位于生活、生产与生态的协调发展,是实现小流域环境改善和可持续发展的根本路径。本研究立足于流域水环境质量改善,以"三生共赢"和可持续发展理念为指导,提出了基于"三生共赢"的小流域水环境综合治理理论架构,即立足于水环境质量改善和水资源的优化配置,强化流域水环境约束,以尽可能小的环境代价支撑流域经济结构优化、新型城镇化发展,以资源高效和循环利用为核心,大力发展循环经济体系和循环社会体系,并通过创新流域治理体制机制构建成本共担利益共享格局,最终实现小流域社会经济可持续发展。本研究基于以上理论架构设计了生态环境、绿色经济、优质宜居三大类指标体系24项具体指标,并重点从优化流域空间开发格局、构建产业绿色发展体系、改善城乡居民生活环境、提升流域生态系统功能、健全流域治理体制机制等方面分析了小流域水环境综合治理对策。本研究可为各级政府创新流域治理模式、制定小流域水环境综合治理规划提供较为可行的理论支撑和技术体系。  相似文献   
109.
Common-pool governance principles are becoming increasingly important tools for natural resource management with communities and comanagement arrangements. Effectiveness of these principles depends on variability in agreements, trust, and adherence to institutional norms. We evaluated heterogeneity in governance principles by asking 449 people in 30 fishing communities in 4 East African countries to rate their effectiveness. The influences of individuals, their membership and role in stakeholder community groups, leadership, community, and country were tested. The membership and role of people were not the main influence on their perceptions of the effectiveness of governance principles. Therefore, drawing conclusions about the effectiveness of specific principles would be difficult to make independent of the individuals asked. More critical were individuals’ nationalities and their associations with the shared perceptions of a response-group's effectiveness of each principle. Perceptions of effectiveness differed strongly by country, and respondents from poor nations (Madagascar and Mozambique) were more cohesiveness but had fewer and weaker between-community conflict-resolution mechanisms. Overall, group identity, group autonomy, decision-making process, and conflict resolution principles were perceived to be most effective and likely to be enforced by repeated low-cost intragroup activities. Graduated sanctions, cost–benefit sharing, and monitoring resource users, fisheries, and ecology were the least scaled principles and less affordable via local control. We suggest these 2 groups of principles form independently and, as economies develop and natural resources become limiting, sustainability increasingly depends on the later principles. Therefore, management effectiveness in resource-limited situations depends on distributing power, skills, and costs beyond fishing communities to insure conservation needs are met.  相似文献   
110.
Wildlife hunting is essential to livelihoods and food security in many parts of the world, yet present rates of extraction may threaten ecosystems and human communities. Thus, governing sustainable wildlife use is a major social dilemma and conservation challenge. Commons scholarship is well positioned to contribute theoretical insights and analytic tools to better understand the interface of social and ecological dimensions of wildlife governance, yet the intersection of wildlife studies and commons scholarship is not well studied. We reviewed existing wildlife-hunting scholarship, drawing on a database of 1,410 references, to examine the current overlap with commons scholarship through multiple methods, including social network analysis and deductive coding. We found that a very small proportion of wildlife scholarship incorporated commons theories and frameworks. The social network of wildlife scholarship was densely interconnected with several major publication clusters, whereas the wildlife commons scholarship was sparse and isolated. Despite the overarching gap between wildlife and commons scholarship, a few scholars are studying wildlife commons. The small body of scholarship that bridges these disconnected literatures provides valuable insights into the understudied relational dimensions of wildlife and other overlapping common-pool resources. We suggest increased engagement among wildlife and commons scholars and practitioners to improve the state of knowledge and practice of wildlife governance across regions, particularly for bushmeat hunting in the tropics, which is presently understudied through a common-pool resource lens. Our case study of the Republic of Congo showed how the historical context and interrelationships between hunting and forest rights are essential to understanding the current state of wildlife governance and potential for future interventions. A better understanding of the interconnections between wildlife and overlapping common-pool resource systems may be key to understanding present wildlife governance challenges and advancing the common-pool resource research agenda.  相似文献   
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